Process for making glue.



UNTTED STATES PATENT OFFICE.

FRANK G. PERKINS, DECEASED, LATE OF LANSDALE, PENNSYLVANIA, BY GER'IRUDES. PERKINS, EXECUTRIX, OF SOUTH BEND, INDIANA, ASSIGNOR TO: PERKINS GLUECOMPANY, A CORPORATION OF PENNSYLVANIA.

PROCESS FOR MAKING GLUE.

f,78,692. No Drawing.

processes for making vegetable glue and more particularly improvementsover the processes claimed in. Reissue Letters Patent No. 13,436 andLetters Patent No. 1,020,656.

According to the processes described in those patents, a suitablecarbohydrate base 2 was first treated to decrease its water absorptive'properties, or so proportion the relative viscosity, cohesiveness andadhesiveness of the resulting product, when the carbohydrate wasdissolved in about three (3) parts of water and a suitable solvent ofcellulose, 'as caustic alkali, that the resulting roduct was suitable toglue up veneers. A ter this preliminary treatment, the carbohydrate wasthen, according to those processes, preferably dried and then dissolvedin caustic and water to form glue. Therefore, in those processes, asmore particularly described, the process was carried out intwooperations, quite. distinct from one another, thus necessitating veryconsiderable time, labor expense. Moreover those processes as generallycarried out were such that the first operation was carried out at onefactory and 315 then the /dried base shipped to the place \wher'e'theglue was to be used, where the second .or last operation was carriedout.

@nemain object of the present invention is to so modify or improve thoseprocesses 40 that the whole process may be carried out in onesubstantially continuous operation in shorter time, and with much lesslabor and expense, and so that large consumers will be enabled to makeuptheir glue from raw carhohlydrate in a simple andeflieien't manner andwithout installing any additional special apparatus.

- The present invention inone form may said to consist suitablymodifying the last step or operation'of the processes. de-

Specification of Letters Patent.

Application filed March 16, 1912. Serial No. 684,298.

Patented Nov. 18, 1913.

scribed in said patents by prolonging the same wlth or without anincrease in temperature whereby the caustic soda alone acts as asubstitute for the caustic soda and peroxid of soda, or as a substitutefor the acid or other suitable starch degenerating agents, to produce inthe glue-dissolving kettle itself, a series of reactions by which theviscosity, cohesiveness and adhesiveness of the carbohydrates, whenfinally dissolved,

flours may be used but in each case the treatment should be slightlymodified in order to adjust it to the particular characteristics of theraw material used. Even the same kindsof starch manufactured from plantsof a different growth or found in a different locality, or even starchesfrom the same plant separated by slightly different processes ofmanufacture, are found to differ sufficiently to require modification inthe treatment. The starches or flours obtained from corn, wheat,potato,.sago palm and the cassava plants have all been tried withsuccess but for most purposes the most convenient and economicalstarches have proven to be those derived from-the cassava plant and soldon the market as cassava flour of the grades M-et, M-5 or Royal.Examples. of the process as carried out with starches known as cassavaM4 and cassava M-5 and Royal, will first be given and then a moregeneral specification will be given, by which anyone skilled in the artmay apply the process to other flours and starches and produce usableresults, and by slight adjustment ofthis general treatment it may bereadily modified toadapt its lf more particularly to the starch inquestion, and produce increasingly satisfactory results, as will beunderstood by those skilled in the art.

Exa1nple 1: 250 pounds'o-f dry cassava flour, grade M4,, is takenandmixed with about 750 parts of water. This mixture is made by firstadding about 300 of the 750 parts of water and stirring thoroughly untilthe mixture is complete, after which the balance of the Water may berapidly added. The whole should then be stirred as thoroughly aspossible for at least one-half hour. Slightly better results arebelieved to be obtained by continuing the stirring or at least allowingthe batch to standat rest over night, and theii stirring up again, butfor commercial purposes one-half hour is all that is regarded asimportant. If it is desired to have a more fluid glue, it is preferredto have the Water heated to about 115 or 120 Fahrenheit when the starchis added, or to have the apparatus arran ed in such a manner that heatcan be gent y applied during the stirring process, and the mass raisedto 100 or 110 by the end of the half hour. If a stiff glue forapplication by specially heavy machinery is desired, this heating may beomitted. To the starch milk as above prepared, and while being stronglystirred and agitated, there is then added with extremely great slowness,6% to 7 per cent. of the weight of the starch of 76 caustic soda or anequivalent quantity of caustic potash dissolved in from 2 to 3 times itsweight ofwater. If more water is used the pro-portion of water in theoriginal mixture should be relatively reduced. If heat is to be omittedand the treatment made,

somewhat more rapidly,'but by the slowness of addition and the degree ofheat applied,

together with the prolonged and violent stirring, the physicalproperties and, it isbelieved, the state of molecular aggregation of thestarch in solution, is so aflected that when put into solution by thecomplete addition of the caustic, the viscosity, cohesiveness andadhesiveness of the resulting mixture Will be those recognized asdesirable for use as a wood glue that is. such thatthe resulting glue iscapable of being applied by machinery and suitable for gluing upveneers. By increasing the temperature used the amount of causticrequired is decreased, and time of operation is shortened.

During the first stages of the operation the caustic is added with suchslowness or in tent suflicient to properly proportion the cohesiveness,adhesiveness and viscosity of the resulting glue, so that it is suitableto glue up veneers; and during the last stages of the operation theaddition of caustic causes the whole carbohydrate to pass over or gointo solution to form such a glue. During the passing over into solutionduring the last stages, it is noticed that the creamy batch has at firsta faint mottled appearance, produced by the dissolving of some of thestarch grains, which mottled appearance gradually increases untilpractically all of the starch has passed over to form a homogeneouscolloidal compound of starch, water and caustic.

Example 2: M-5 cassava flour mixed with 2% times its Weight of water, towhich ,has'

been added heat enough to raise it to about 140 Fahrenheit, is slowlytreated with a solution of 2 per cent. of its weight of 76 caustic sodain from 2 to 3 parts of water,- the rate of addition of the causticsolution being such as to occupy about 20 minutes, during which time thetemperature shall be maintained and preferably raised to 150 0r 160Fahrenheit.

Example 3: The grade of cassava flour sold on the market as Royal issuspended in 2% times its weight of water by constant stirring and whilecontinuing the stirring, heat is applied, or the original water may havebeen heated to such a temperature that the temperature of the resultingmixture when made, approximates 100 Fahrenheit.

The batch is stirred for of an hour at substantially this temperatureand there is then added to it 7 per cent. of the'weight of the starch,of caustic soda in the form of a solution in three parts of water, thetemperature and stirring being maintained throughout this time, and thecaustic solution added at a rate such that the addition of the solutionoccupies about 3 hours, during at least the first half ofwhich thetemperature is maintained above 100.

The above examples are given as specific Tor certain product-s.stantially equable addition of solution of caustic is advantageous forordinary practical purposes. It seems that the effect of the caustic inthe first stages is most satisfactory and rapid when the caustic itselfis present in such proportions that the mix ture will assume a whitecreamy consistency, a". 6., that some small portion of the starchgranules are dissolved. The action of a portion of the starch dissolvedin the caustic soda appears to be similar in character'to.

The gradual and subdissolved. Since it requires a little more skill totake advantage of this process of treating the starch, a final exampleillustrating a method more generally applicable 4 times its weight ofwater,

manner that'when the stare that the treatment has been such incense toother suitable starches that have been; tried so far, will be given. l

Example 4: Any suitable starch or flour mixed up to a mi k, with from 2to about according to the density of glue "desired, and heated to 130Fahrenheit by such gradual ap lication of heat that the starch itselfshail not be tumefied, is then treated with constant stirring byaddition of about 4 er cent. of its weight of 76 caustic soda issolvedin three parts of water to one of caustic soda. With some starches allof this t per cent. may not be required, and with some others, slightlymore, but the addition of the caustic soda solution is continued to thatpoint where the batch while being stirred assumes the white creamyconsistency, but does not show much tendency to agglutinate intransparent masses of considerable size. When this point is reached andwhile maintaining the temperature, stirring is continued for fromone-half to g of an hour, after which an additional amount ofsimilar-caustic soda solution is added to bring the total amount ofcaustic soda up to about 7 to 10 per cent. In other words, about 3 to 6per cent. more of caustic is added tothe batch, after which the batch isthoroughly stirred for a short time to put the carbohydrate intosolution and to equalize its consistency and composition, and then thebatch is preferably allowed to stand for an hour or two before used as aglu It will be obvious in all these examples,

as to perunit a portion of the caustic soda used, to act either alone ortogether with heat, upon the 'lmdiss'olved starch granule, for a rioddepending-on the strength of the caustic and the temperature used. It isbelieved that a certain portion of the outside integuments of the starchgranules, 6., the portion having, the higher molecular weight, isdissolved during this..-preliminary treatment, and distributedthroughout the li uid in such a granule itself is dissolved by theinterior portion being liberated and passing into solution, thevisacuity of the two is equalized and possibly some forfn of atedbetween the two in the viscous colloidal liquid produced in such amanner that the meanryiscosity, cohesiveness and adhesiveness of themixture is properly proportioned to produce gluehavin a finaladhesiveness D i of being applied by machinery, the total when properlyapp'lie' and. dried,-substansuitable tially as great as thebest animalglue and or gluingveneers. 5'

the action is exclusive upon the granule, or -whether there is somecombined action between the various ars r the granule asjust indicated,is not certain, but certainly a different and much molecular combinationgenerportion the viscosity, cohesiveness and ad:

more iprcfound h nge s iproduced by the slow addition or prolongedaction of the caustic, or addition of the caustic in small quantitiesa-t first 4 together with temperature) than the t difference of rate inadding the caustic soda solution would be expected to yield. In otherwords, it is found that starches which when dissolved in the ordinarymanner in caustic soda would show products with such a viscosity that itwould be impossible to use them satisfactorily as glue to be applied bymachinery, yet when dissolved in this way by the .extremely slowaddition of caustic together with a suitable temperature, in case it isdesired to hasten the action of the caustic, produce semi-fluid glueswhich can conveniently be applied by machinery and which have all thedesired valuable properties of the animal glue for flat glulng, such aslui lso t at diflerent starches require difi'erent treatment, but thatthe same underlying principles control the application, which rmclpleswill be readily applied by those Ski ed in i the art, from the examplesabove given, to

other starches of somewhat difierent character. It is therefore clearthat the invention in its broader aspects is not limited to theparticular carbohydrates, temperatures or percentages stated, nor to theuse of caustic soda alone, .as other carbohydrates such as certaingrades of celluloses or hemi-celluloses, and other temperatures andpercentages, and other caustics such as caustic'potash .and othersolvents of cellulose, suchas for instance vsodium xanthate, sodiumsilicate, zinc chlorid and basic'lead acetateiwill readily suggestthemselves tothose slnlled in the art to meet the peculiar exigencies ofeach case. 7

Having fully and clearly described the invention, what is claimed as newand what is desired to be secured by Letters Patent, is

1. The improved process of making glue,

which consists insuspendin cassava carbohydrate in 'waterand then ading, with-sub.- sta-ntially continuous stirring, a SOlUtJQIL of causticalkali with such slowness that tumefyin-g or bursti of the firststages-of the treatment, topic? hesiyeness of the resultingglue, so.that upon passes over into a semi-fluid glue capable j amount of waterin the glue being about 4 Whether i that of'the caustic 1 parts or lessby weight of dry carbohydrate.

2. The improved process of making wage-J ttable glue which consists insuspending i-suitable vegetable carbohydrate 111 water, and

then'treating the batch with-such an amount -of;a.so1vent of cellulose,as caustic alkali, that 'tumefying ior {bursting .o'fthe carbohy- -ofthe carbohydrate as a" a whole is avoide during a substantial part drateas a'whole is avoided, and such that the viscosity, cohesiveness andadhesiveness of the resulting glue is so proportioned as to make itsuitable to glue up veneers, and then adding more solvent of celluloseto the batch until the batch passes over into a semi-fluid glue capableof being applied by machinery, and suitable for gluing up veneers.

3. The improved process of making a wood mal glue.

4. The improved process of making a wood glue, which consists insuspending a starchy carbohydrate in water, then agitating or stir- Iring the batch'and adding caustic alkali in such an amount thattumefying or burstin of the carbohydrate as a whole is avoide and suchthat the viscosity, cohesiveness and adhesiveness of the resulting glueis so proportioned as to make it suit-able to glue up veneers, and thenagitating or stirring the batch and adding more caustic until it passesover ,into a semi -fluid glue capable of being applied by machinery, andsuitable for gluing up wood veneers, the total amount of water usedbeing about 4 parts or le$ by weight of dry carbohydrate.

5. The improved process of making vegetable glue, which consists insuspendinga suitable vegetable carbohydrate in' water, heating the batchto about 100: Fahrenheit or more, and then treating the batch withapplied by machinery, and suitable to glue such a quantity of. a solventof cellulose, as caustic alkali, that tumefying or bursting of thecarbohydrate as a whole is avoided, and such that the viscosity,cohesiveness and adhesiveness of the resulting glue is so proportioned.as to make it suitable to glue up veneers, and then adding more of thesolvent of cellulose to the batch until the batch passes over into asemi-fluid glue capable of being up wood veneers.

6. The improved process of. making a wood glue, which consists insuspending a starchy carbohydrate in Water, then agitating or st-irrinthe batch and addingycaust-ic alkali in suc amount that tume ing orburstin of the carbohydrate as a whole is avoide and such that theviscosity, cohe-- siveness and adhes veness of the resulting glue is soproportioned as to makeit suitable to glue up veneers, and thenagitating or stirring the batch and adding morecaustic until it passesover into a semi-fluid glue capable of being applied by machinery andhaving a final adhesiveness substantially as great as good animal glue,the total amount of water used being about 3 parts or less by weight ofdry carbohydrate, and the batch being heated to about 1009 Fahrenheit,or more.

7. The improved process of making vegetable glue, which consists insuspending a suitable vegetable carbohydrate in water, and stirring thebatch for about one-half hour or more, and then treating the batch withsuch small quantities of a solvent of cellulose, as caustic alkali, thattumefying or bursting of the carbohydrate as a whole is avoided, andsuch that the viscosity, cohesiveness and adhesiveness of the resultingglue is so proportioned as to make it suitable to glue up veneers, andthen adding more solvent of cellulose to the batch until the batchpasses over into a semi-fluid glue capable of being applied bymachinery, and suitable for gluing up veneers.

8. The improved process of making vege table glue which consists insuspending cassava carbohydrate in water, and stirring the batch forabout one-half hour or more, and then heating to about 100 Fahrenheit,or more, and treating the batch with such small quantities of a solventof cellulose, as I caustic alkali, that tumefying or bursting of thecarbohydrate as a whole is avoided, to proportion the viscosity,cohesiveness and adhesiveness of the resulting glue, so that it issuitable to glue up veneers, and then adding more of the solvent ofcellulose to the batch until the batch passes over into a semifiuid gluecapable of being applied by machinery, and having an adhesivenesssubstantially as great as good animal glue, the total amount of waterused being about 4: parts or less by weight of dry carbohydrate.

9. The improved process of making vegetable glue, which consists intreating a suitable vegetable carbohydrate with water and with such anamount of a solvent of cellulose that tumefying or bursting of thecarbohydrate as. a whole is avoided, and such that the viscosity,cohesiveness and adhesiveness of the resulting glue are so proportionedas to make'it suitable to glue up veneers, and then further treating thebatch with said solvent until the batch passes over into a semi-fluidglue capable of being applied by machinery, and suitable for gluing upveneers.

10. The improved process of making vegetable glue, which consists intreating a suit able vegetable carbohydrate with water and with such anamount of a solvent of'cellulose that tumefying or bursting of thecarbohydrate as a whole is avoided, and such that theviscosity,cohesiveness and adhesiveness of the resulting glue are so proportionedas to make it suitable to glue up veneers, and then further treating thebatch with said solvent and with additional heating until the batchpasses over into a semi-fluid glue capable of being applied bymachinery, and suitable for gluing Wood.

In testimony whereof I have signed my 1 name to this specification inthe presence of two SllbSCI'lblIlg Witnesses.

GERTRUDE S. PERKINS,

GORHAM CROSBY, EDWIN SEGER.

